The long-awaited Intel Conroe processors have finally been announced. We will start our Conroe family performance investigation with the youngest model in the family. This review will reveal the most extensive performance analysis, overclocking experiments and a detailed review of one of the first mainboards supporting the promising newcomer.

July 13, 2006 will undoubtedly enter the world’s computer history as the arrival of revolutionary desktop processors with Intel Core microarchitecture. The thing is that this event is very meaningful for the entire market. This day has every chance to radically change the situation in the market, just like September 23, 2003, when AMD launched their Athlon 64 processors and thus turned into a technology leader. Intel that has been struggling with quite a bit of trouble caused by their NetBurst architecture during the past few years, has finally given up the idea of developing it any further and decided to return to the roots of things. Namely they will continue enhancing and developing their P6 architecture that was first introduced in Pentium Pro processors. Of course, it doesn’t mean that the new CPUs announced today are exactly like their predecessors. The microarchitecture has undergone significant changes and modifications since the first time they released it. It was first implemented in Pentium II processors, then in Pentium III, after that it migrated to the mobile Pentium M and Core Duo CPUs. Every first reincarnation of this microarchitecture acquired new features and improvements, in order to make it fit for the new processors.

Moreover, Core 2 Duo processors that are announced today should boost the desktop x86 processors performance quite tangibly. Intel engineers did a great job working on the new microarchitecture, and as a result, the new solutions can now boast a few truly remarkable advantages over the predecessors as well as competitors.

You can read more about the peculiarities and specifics of the Core microarchitecture used for Core 2 Duo processors also known as Conroe in our theoretical article called Getting Ready to Meet Intel Core 2 Duo: Core Microarchitecture Unleashed. Today I would only like to note that Core 2 Duo is the first x86 processors that can decode and execute 4 commands per clock cycle and moreover, process 128-bit SSE3 instructions without slowing down. These two advantages are the two major factors determining high performance of the new Core 2 Duo CPUs, which we have already seen in numerous previews posted on the web.

Moreover, I have to stress that Core 2 Duo processors can boast “truly” dual-core design. With a few allowances, Pentium D and Athlon 64 X2 can be characterized as a combination of two independent cores put together onto a single semiconductor die. The dual-core concept is much more in-depth in the new Intel CPUs. These processors features a single cache shared between the two cores, which has made data exchange between the cores much simpler. In particular, this solution allowed reducing the latencies when both cores work with the same set of data.

In other words, the focus is on the number of operations the Intel Core 2 Duo processors can perform per clock cycle. It means that Intel has finally terminated the failed “hunt for GHz” and is now betting on the processor efficiency. As a result, we can expect the new processors to be not only fast but also economical that logically follows from the fact that there are a lot of mobile solutions among their direct predecessors.

This article is going to be the first chapter in the series of works devoted to the practical analysis of the features and performance of the new promising solutions. I have to stress that, just like Intel, we decided to use a somewhat innovative approach to the practical tests of Core 2 Duo this time. Since the performance level of Core 2 Duo and Core 2 Extreme has already been covered very well by our colleagues from other online resources, we decided to slightly postpone the tests of the top processor models from the new family. Instead we suggest taking a closer look at the performance and efficiency of the youngest Core 2 Duo model that is very likely to become even more popular than its elder brothers thanks to a very attractive and democratic price of $183. We are going to compare its performance with that of competitor’s solutions from the same price range and will pay special attention to overclocking as a very popular way of getting more performance for your buck. By the way, this allows us to introduce to you one more hero of the day: the new ASUS P5W DH Deluxe mainboard, one of the few platforms available in the today’s market that supports Core 2 Duo processors and boasts quite impressive set of overclocking friendly features.

Closer Look: Core 2 Duo E6300 Processor

The processor family based on Core microarchitecture currently consists of five models:

CPU

Clock speed, GHz

L2 cache, MB

Bus frequency, MHz

Typical heat dissipation, W

Price, $

Core 2 Extreme X6800

2.93

4

1066

75

999

Core 2 Duo E6700

2.67

4

1066

65

530

Core 2 Duo E6600

2.4

4

1066

65

316

Core 2 Duo E6400

2.13

2

1066

65

224

Core 2 Duo E6300

1.86

2

1066

65

183

The top of the line Core 2 Extreme processor is targeted for the highest-performance computer systems, while other solutions are positioned for high-end and mainstream systems. If you look at the pricing, you will see that Core 2 Duo E6300 boasts the best price-to-frequency ratio (that is the major factor influencing the performance of the solutions within the same family). This is also one of the reasons we are so interested in taking a closer look at this processor.

However, unlike the top processor models, Core 2 Duo E6300 (just like Core 2 Duo E6400) features 2MB of L2 cache memory. Although our tests indicated that the L2 cache memory size doesn’t have that much effect on the overall performance of the Core microarchitecture based processors:

Core 2 Duo1.86GHz, 2MB L2

Core 2 Duo1.86GHz, 4MB L2

Performancedifference

SuperPi, sec

321.652

318.891

0.9%

3DMark

5658

5672

0.2%

3DMark06, CPU

1659

1670

0.7%

AutoGK 2.27/DiVX 6.2, fps

40.23

40.81

1.4%

Adobe Photoshop CS2, sec

132

129

2.3%

WinRAR 3.6

1150

1216

5.7%

CINEBENCH 9.5, Rendering

572

579

1.2%

F.E.A.R.

150

158

5.3%

Quake4

105.3

107.9

2.4%

We can notice a slight performance difference in WinRAR that works actively with the data. It is about 6% here. F.E.A.R. game is also approaching the same value. In all other cases the performance gain resulting from twice as big L2 cache memory doesn’t exceed 2%-3%. Therefore, hunting for CPU models with 4MB L2 cache is hardly worth the trouble and effort.

Besides the lower clock speed (it is 1.86GHz for Core 2 Duo E6300) and smaller L2 cache, there are no other differences between the youngest model of the new family and the top-of-the-line solutions including Core 2 Extreme. It boasts all the strengths of the Core microarchitecture based products:

Dual-core design . The CPU combines two independent cores working in parallel within the same packaging. These cores work at the same clock speed and share 2MB L2 cache. They are connected to the chipset using the same Quad Pumped Bus working at 1066MHz frequency and featuring 8.5GB/s bandwidth.

Intel Wide Dynamic Execution . Each of the two processor cores can process four instructions per clock cycle.

Intel Advanced Smart Cache . Intellectual L2 cache is shared between the two processor cores depending on their load at the given moment of time. Moreover, the shared L2 cache speeds up data transfer rate between the cores and reduces the front side bus workload, because no data needs to be transferred via the system memory any more.

Intel Advanced Media Boost . The processor works faster with SSE3 instructions because it can perform the binary operations with 128-bit SSE registers within one clock cycle.

Intel Virtualization Technology (Intel VT) . This virtualization technology allows modeling the work of several virtual platforms on a single hardware system.

Intel Enhanced Memory 64 Technology (Intel EM64T) . The processor supports x86-64 extensions that allow addressing over 4GB of system RAM and support the work with 64-bit general purpose registers.

Execute Disable Bit . The OS is protected against harmful spyware and viruses that use “buffer overflow” error to gain control over the system.

Lower heat dissipation and power consumption . Core 2 Duo processors are manufactured with the newest 65nm technological process. Thanks to their architecture and a number of power saving technologies they boast the typical heat dissipation of 65W.

The formal specifications of the Intel Core 2 Duo E6300 processor that we tested in our lab look as follows:

Intel Core 2 Duo E6300

Clock speed

1866 MHz

Processor packaging

LGA775

Vcore

0.85-1.3625 V

Bus frequency

1066 MHz

Typical heat dissipation

65 W

Max. case temperature

100o C

L2 cache

2MB, shared

Production technology

65 nm

Intel Hyper-Threading support

None

Intel Virtualization Technology

Yes

EM64T (Enhanced Memory 64 Technology)

Yes

EIST (Enhanced Intel SpeedStep Technology)

Yes

Just like all the other CPUs from the Core 2 Duo/Core 2 Extreme family, the youngest processor model is also based on the Conroe core.In fact, this processor will be built using two cores with full-size cache memory, and half of it will later be disabled at the packaging stage.

In other words, Core 2 Duo E6300, like the rest of the new desktop processor family, features a 144sq.mm die consisting of 291 mln transistors. So, from this standpoint the new CPU is somewhat simpler than the predecessor on the Presler core – Pentium D processor that featured 376 mln transistors and a core with total die size of 162sq.mm. However, we shouldn’t forget that Presler consists of two physical dies put together into a single package, while Conroe is of solid design. Therefore, the production costs of Core 2 Duo will be higher for Intel. Another piece of evidence proving this fact is the anticipated dramatic drop of Pentium D retail prices, which should happen any day now.

Let’s take a look at the info on the new processor that we read from the CPU-Z diagnostic utility:

As you can see from the screenshot, the CPU is based on B0 core revision. This is not the latest revision out there. The processors that will start selling will feature Conroe core revision B2. I also feel it is important to explain why this utility recognizes our processor as Allendale. The thing is that they use this name for the lower-price Conroe modification with the L2 cache memory cut down to 2MB. In other words, exactly for the Core 2 Duo E6300 and E6400 processors. BY the way, Conroe and Allendale are not the only two codenames that you may come across in reference to the new Core microarchitecture based solutions. There is one more name – Millville. This name stands for the budget single-core CPU models.

The clock frequency multiplier in Core 2 Duo E6300 is 7x. With 266MHz FSB frequency it provides the 1.86GHz clock speed. Note that this multiplier can be reduced to 6x, because the processor supports Enhanced Intel SpeedStep technology. In case of lower workload, the processor frequency can drop down to 1.6GHz and its typical heat dissipation can be reduced to 22W.

Although Core 2 Duo processors are designed in LGA775 form-factor and support Quad Pumped Bus at 1066MHz, which is common for Pentium 4/Pentium D CPUs, they are incompatible with the old mainboards. The problem lies with the Vcore of new Core 2 Duo processors that is different and moreover, can be adjusted with a smaller increment. Therefore, you need more than just the support of the new processors in the mainboard BIOS. The voltage regulator on the new mainboards should comply with the VRM 11 specification. At this time there are very few mainboards in the market that meet these requirements, however, the situation will certainly change in the nearest future. Especially, since Intel is also launching its new P965 Express chipset together with the Conroe processor family. At this time, the few mainboards supporting new processors are based on the Intel 975X Express chipset and are none other but the updated modifications of the existing platforms. However, despite this fact there are a couple of mainboards out there that are worth your attention. That is why we are eager to devote the whole chapter of our article to a solution like that: ASUS P5W DH Deluxe mainboard.

Closer Look: ASUS P5W DH Deluxe

It is very important to select the right mainboard for the new Intel Core 2 Duo processor. At least at this time, when there is not much of a choice and even the available products are not absolutely perfect. In fact, there are only two mainboards available at this time that will suit the hardware enthusiasts. They are – Intel D975XBX Bad Axe revision 304 (other modifications of this mainboard do not support Conroe processors) and ASUS P5W DH Deluxe.

I have to point out that even if you are an overclocker, you should still consider Intel mainboard as a possible option. Strange as you might think, but Intel D975XBX Bad Axe is very different from other similar mainboards designed by Intel. It boasts a few pretty decent options for CPU overclocking, including processor Vcore and Vmem adjustment as well as raising the FSB frequency to 400MHz. moreover, D975XBX Bad Axe allows performing a lot of modifications that will turn it into an even better overclocking tool.

Nevertheless, we decided to select ASUS P5W DH Deluxe for our today’s review. It offers a list of advanced overclocking-friendly features that are available immediately without any additional modifications. Besides, ASUS has well-established reputation among hardware enthusiasts. This gives us very good reason to believe that P5W DH Deluxe will prove an ideal platform for the new Intel processor.

So, let’s take a closer look at the new solution from ASUS. P5W DH Deluxe is based on a relatively old Intel 975X Express chipset that remains the fastest solution for the high-end systems in the market today. Even though the new Intel P965 Express is equipped with a more enhanced ICH8 South Bridge, it is positioned for the mainstream systems in the first place. That is why ASUS decided to go with the i975X for their top mainboard product.

We have already come across a few older ASUS solutions on the i975X chipset before. However, they were not intended to support Intel Core 2 Duo processors and didn’t have the VRM 11 compliant CPU voltage regulator circuitry. Therefore, ASUS P5W DH Deluxe can be regarded as a new revision of a well-known and beloved solution – ASUS P5WD2-E Premium, even though it might not be absolutely correct to say so. The new mainboard boasts some serious design changes and a number of new features that distinguish it clearly from the predecessor. Juts look at the official mainboard spec, and you will see the difference right away:

As you can see from the table above, the manufacturer paid special attention to networking and data storage features of the ASUS P5W DH Deluxe mainboard. This platform boasts a few principally new algorithms and interfaces that allow connecting hard drives and creating RAID arrays a lot easier and faster. These features as well as the remote control unit that comes with the board allowed ASUS to announce this product within their Digital Home product category. The name of the mainboard also stresses this positioning by the “DH” abbreviation.

ASUS P5W DH Deluxe can be considered a pretty universal product in terms of supported processors and memory as well as expansion options. This board can work with any LGA775 processors, including the old 90nm models as well as the new CPUs with Core microarchitecture. I would like to specifically mention that this mainboard will also be compatible with the quad-core Kentsfield processors that are coming out in Q1 2007.

ASUS P5W DH Deluxe features four slots for DDR2 SDRAM that are located in pairs, each assigned to separate memory channels. Note that besides the officially supported DDR2-533/667/800 SDRAM, the board also allows installing faster DDR2-1067 memory, though this support is not official at this time. The memory bus, however, can only work at this frequency with the CPUs running at 266MHz FSB.

It is very nice that ASUS engineers paid special attention to the expansion slots on the board. Besides the two PCI Express x16 graphics slots (supporting ATI CrossFire technology), there is a pair of PCI Express x1 slots and three (which is a very rare thing for contemporary mainboards) PCI slots.

Among the common features of ASUS P5W DH Deluxe we should mention 8 USB 2.0 ports and two FireWire ports. The chipset ensures the functioning of the USB 2.0 bus, while the FireWire is implemented via the onboard controller from Texas Instruments. The mainboard back panel carries four High-Speed USB ports and one IEEE1394a port. All other ports have been laid out on the PCB as pin-connectors, so you can install special additional brackets with two USB and one FireWire ports that are supplied with the mainboard. Note that one of the USB ports laid out on the mainboard back panel is intended for the infra-red signal receiver that is bundled with the P5W DH Deluxe, so that you could use the remote control unit.

The integrated sound solution based on the eight-channel High Definition Realtek ALC882M codec also has its peculiarities. Thanks to the MP3-In technology, the mainboard allows you using its Line-In even when the system is shut down. The signal will anyway be transferred to the acoustic system. Moreover, this codec boasts one more remarkable feature: it can play two different sound streams independently. In this case one stream will go through 7.1 acoustic system, while the other one will go through the stereo headphones. The codec enabled 6 audio-jack connectors on the mainboard back panel, as well as optical and coaxial SPDIF Outs.

The mainboard engineers paid special attention to the networking capabilities of this product. As we have already mentioned, P5W DH Deluxe features two Gigabit network controllers from Marvell, however ASUS engineers have also implemented a wireless WiFi controller from Realtek that supports IEEE 802.11g standard. This controller is physically laid out on a small add-on daughter card that accommodates an antenna also bundled with the board. The controller comes with special software that allows using it as an access point as well as a station.

The most exciting feature of ASUS P5W DH Deluxe is the implementation of Serial ATA interfaces. The first thing that catches your eye is that there are only three SATA-300 connectors that lead directly to the ICH7R South Bridge, while the chip clearly supports four ports. The explanation of this phenomenon lies with the Silicon Image 4723 chip that is none other but a dual-port Serial ATA-300 controller connected to one of the Serial ATA-300 interfaces of the board. In other words, one of the ICH7R ports is allocated for the controller offering two additional ports. This two-level connection has one very important advantage: the RAID arrays built with Silicon Image 4723 controller do not require any driver installation, thus making initialization very simple and quick. This is how ASUS implemented EZ-Backup function: if you connect two identical hard disk drives to the SATA-300 ports of the Silicon Image controller, you will automatically get a RAID 1 array. In fact, this controller also supports RAID 0, however, the use of this array type will not be the most optimal solution in this case. If you connect two hard disk drives via the same single Serial ATA interface, it will limit their performance.

There is another Serial ATA controller onboard ASUS P5W DH Deluxe: JMicron JMB363. This chip supports one PATA-100 interface and two SATA-300 ports. One of the ports has been laid out on the mainboard PCB, while another one is available on the mainboard back panel as eSATA connector. This way, the mainboard offers the total of 7 SATA-300 ports and 2 PATA-100 ports. And you will be able to create RAID 0, 1, 5 and 0+1 from the hard disk drives connected to this mainboard.

Of course, it was a hard task for the designers to conveniently locate all these controllers on the mainboard PCB. However we should give them proper credit for they have done a great job: we don’t have anything to criticize about the PCB layout. On the contrary, there are a few evident advantages that deserve our special mention.

First of all, we would like to stress the convenient location of all expansion slots. Although there are quite a few PCI and PCI Express slots on the PCB, the DIMM slots latches do not catch on the installed graphics cards. Moreover, PCI Express x16 slots are placed at quite a distance from one another, thus ensuring better thermal conditions in case of two graphics cards installed.

The second advantage of ASUS P5W DH Deluxe is a high-quality eight-phase processor voltage regulator built with Nichicon electrolytic capacitors.

The third great feature is the smart heat dissipation scheme for all high-heating components of the mainboard. The chipset South Bridge is covered with a low-profile copper heatsink. The chipset North Bridge is equipped with a much larger copper heatsink. Besides they used a heatpipe to connect it to the copper heatsink of the processor voltage regulator circuitry. In order to avoid using any active cooling (and the i975X chipset starts heating up quite noticeably when working with 266MHz FSB), the heatsink of the CPU voltage regulator is positioned in such a way that the airflow from the processor cooler reaches it and cools down. ASUS even took care of those users who have passive CPU cooling solution or a liquid-cooling system installed. The mainboard is bundled with an additional fan that can be installed onto the heatsink behind the processor socket if needed.

The back panel of the ASUS P5W DH Deluxe mainboard is pretty standard for contemporary solutions. It carries four High-Speed USB ports, two RJ45 network connectors, FireWire port, PS/2 ports for keyboard and mouse, six audio-jacks, a coaxial and an optical SPDIF outs, one serial port and a WiFi antenna connector.

We discovered quite a few interesting technologies in the BIOS Setup of ASUS P5W DH Deluxe mainboard. First of all, I would like to mention EZ Flash 2 technology that implies that there is a special BIOS reflashing code integrated directly into the BIOS itself. Note that this utility can read reflashing files not only from floppies, but also from USB flash drives, which makes even more useful in the long run.

In case the BIOS reflashing still fails, there is CrashFree BIOS 3 that will come to rescue. It will restore the corrupted BIOS code from the file on your floppy disk or USB keychain.

Hardware monitoring is also implemented quite decently. Of course, ASUS P5W DH Deluxe allows monitoring the usual parameters such as CPU and environment temperature, major voltages and rotation speeds of five fans. However, ASUS P5W DH Deluxe can also adjust the fan rotation speeds basing on the status of the monitored parameters. This function is implemented with the help of Q-Fan 2 technology. Here I have to say that I had some concerns about the temperature measuring algorithms for the processor core. For some reason ASUS didn’t use the data from the digital diodes built into the new Conroe processors. Instead they used an analogue thermal diode and moreover, the reported temperatures were considerably lower than the actual ones.

ASUS offers the traditional PC Probe II utility to monitor the mainboard status directly from Windows. This utility works great with the new platform.

And of course, they couldn’t help implementing the AI NOS dynamic overclocking technology in the BIOS Setup. Unlike similar technologies from other manufacturers, AI NOS’ decision whether or not to increase the processor frequency is based on the processor’s power consumption rather than temperature. As a result, we get faster and more precise reaction to the actual situation. The mainboard also supports Intel Enhanced SpeedStep technology that can even be enabled together with AI NOS.

Automatic overclocking is good, but we are certainly much more interested to see how ASUS P5W DH Deluxe copes with manual processor overclocking. Luckily, the board offers a lot of overclocking-friendly options:

Adjustable FSB frequency in the interval from 100MHz up to 450MHz;

Independently adjustable PCI Express frequency in the interval from 90MHz to 150MHz;

Possibility to lock the CPI frequency at the nominal value of 33.3MHz;

Adjustable Vmem in the interval from 1.8V to 2.4V with 0.05V increment;

Adjustable processor Vcore that can be set in the interval from the nominal value up to 1.7V with 0.0125V increment;

Adjustable FSB Termination voltage that can vary from 1.2V to 1.5V with 0.1V increment;

The voltage on the chipset North Bridge can be adjusted from 1.5V to 1.65V with 0.05V increment;

The voltage on the chipset South Bridge can be set to 1.05V or 1.2V.

Unfortunately, despite this relatively long list of overclocking-friendly options of ASUS P5W DH Deluxe, they may not be enough in some cases. Our biggest concern is the relatively low maximum FSB frequency. Although 450MHz FSB may be more than enough during Celeron D, Pentium 4 or Pentium D overclocking, it will be fairly easy to hit the maximum when working with Core 2 Duo processors. The thing is that Core 2 Duo processors work at relatively low clock speeds, but use high bus frequency. As a result, we get very low clock speed multipliers, that are 7x and 8x by the youngest Conroe models respectively. Therefore, we may need to raise the bus frequency even higher than what the BIOS Setup of ASUS P5W DH Deluxe mainboard can offer us.

However, don’t give way to despair: there is a solution to this problem. It is the well-known ClockGen utility that allows increasing the FSB frequency on ASUS P5W DH Deluxe up to 500MHz from Windows.

As for the other features that could be of interest to computer enthusiasts, we would like to mention the options for memory subsystem configuring. ASUS P5W DH Deluxe mainboard allows changing the major timings and dividers for the memory bus and FSB frequencies. Note that this platform offers a very extensive set of FSB:Mem dividers. For the FSB frequencies of 266MHz+ we get 4:3, 1:1, 4:5, 3:8, 2:3, 3:5, 1:2.

Summing up everything we have just said, we can conclude that ASUS P5W DH Deluxe is a true solution for overclockers and enthusiasts. Let’s see how good it turns out together with the new Intel Core 2 Duo E6300 in our practical test session. Of course, the most exciting part of our session will be connected with overclocking. So let’s get down to it right now.

Core 2 Duo E6300 Overclocking

When we just started working on this material, we expected to overclock the youngest Intel Core 2 Duo model to phenomenal heights. And we had very good reasons to believe so. The thing is that there are a lot of overclocking reports on the web these days about successful overclocking of Core Microarchitecture based processors. And in most of those stories the users managed to nearly hit 4GHz frequency with none other but air cooling. If the youngest Core 2 Duo E6300 processor with 1.86GHz nominal frequency manages to hit this mark, we will be able to claim unprecedented result: doubling of the CPU speed.

However unfortunately, our expectations didn’t come true. The thing is that the clock frequency multiplier of Core 2 Duo E6300 processor is locked at 7x. That is why we would have to increase the FSB frequency to 571MHz in order to hit the 4GHz core speed. And this isn’t possible for at least two reasons. First, the current clock frequency generators allow overclocking the FSB up to 500MHz maximum. Second, the mainboard should use only super-high-quality components and be designed very thoroughly to ensure that it can retain stability at these speeds. If the second obstacle doesn’t seem that drastic, then the first one is still insurmountable.

However, we stumbled upon some problems long before the FSB speed hit 500MHz mark. And our experiments with ASUS P5W DH Deluxe mainboard revealed it very clearly.

Before we start sharing the obtained results, let me say a few words about the configuration of our test platform. Besides the Intel Core 2 Duo E6300 processors and ASUS P5W DH Deluxe mainboard we also used 2 GB of DDR2-800 memory: Corsair TWIN2X2048-6400C4. The system was also equipped with PowerColor X1900 XTX 512MB graphics card. The processor was cooled down with a Zalman CNPS9500 LED cooler, although this was an absolutely unnecessary measure, because the heat dissipation of Core 2 Duo processors is much lower than that of NetBurst based CPUs.

As for the actual Core 2 Duo E6300 processor overclocking, it was performed in a pretty traditional manner. In other words, these CPUs can be overclocked as easily as their predecessors. Especially since the frequency potential of Conroe processors is really huge.

Nevertheless, during our overclocking experiments on ASUS P5W DH Deluxe mainboard we faced two typical problems that may become the main stumbling stones for those who will ever try overclocking the youngest Conroe models.

The first problem surfaced when we got close to 400MHz FSB frequency. Any further frequency increase would prevent the mainboard from booting. It had evidently nothing to do with the CPU, because Vcore increase didn’t affect the situation in any way. We discovered, however, that at this high bus frequency chipset North Bridge fails, although Intel uses pre-selected most stable and reliable chips for its i975X core logic. The problem can be resolved easily by raising the chipset MCH voltage.

Therefore, you should make sure that the i975X mainboard you choose for overclocking experiments with the new Core 2 Duo processors allows increasing the voltage on the chipset North Bridge. At the same time, you should also check the North Bridge cooling system. When the FSB frequency increases significantly, as well as the MCH voltage, the North Bridge chip may get really hot, and even reach dangerous levels if the cooling solution is not efficient enough.

The second problem we encountered during Core 2 Duo overclocking is very closely connected with the first one. Although the MCH voltage increase improves the mainboard overclocking potential, we still wish we could squeeze more out of it. On average, every 0.05V increase results into additional 7-8MHz. As a result, if you want to use up the entire clock generator potential that theoretically supports up to 500MHz FSB frequency, you should raise the voltage on the chipset North Bridge up to 1.85-1.9V. The maximum voltage setting allowed in the mainboard BIOS Setup is only 1.65V. This is the major limiting factor for successful Core 2 Duo overclocking.

As a result, if we set the chipset North Bridge voltage to the maximum, the mainboard would work stably only at 420MHz FSB. We couldn’t get beyond this value for the reasons described above. As for the CPU, its frequency potential was very far from being exhausted. Even with the clock speed of 2.94GHz that was reached as a result of our overclocking experiment, it was still working absolutely stably at its nominal Vcore.

However, I don’t think you should be upset about the not very high frequency we achieved today. Core 2 Duo E6300 overclocked on ASUS P5W DH Deluxe by more than 50%, which is a very good result. At the same time we managed to surpass (though not tremendously) the nominal frequency of the top-of-the-line model in the family – the Core 2 extreme X6800. Keeping in mind relatively low influence of the cache memory size on the overall performance, we can state that for less than $200 you can get a CPU running close to a 1000-dollar model.

After these optimistic statements, I believe it is high time we took a closer look at the actual benchmark results.

Testbed and Methods

In order to select worthy competitor for our main hero, Core 2 Duo E6300, we should take a real close look at the new CPU prices the thing is that together with the launch of Core 2 Duo processor family, Intel dropped the prices of its dual-core solutions on NetBurst architecture. Of course, this Intel’s action will not remain unnoticed by its major rival, the AMD Company, which is going to reduce the prices of its dual-core processors quite aggressively in the nearest future. We assume that the processor price-list including dual-core solutions from AMD and Intel will very soon look as follows:

CPU

Specs

Price

AMD Athlon 64 FX-62

2.8GHz/2x1MB L2

$1031

Intel Core 2 Extreme X6800

2.93GHz/4MB L2/1066MHz FSB

$999

Intel Core 2 Duo E6700

2.66GHz/4MB L2/1066MHz FSB

$530

AMD Athlon 64 X2 5000+

2.6GHz/2x512KB L2

$403

Intel Core 2 Duo E6600

2.40GHz/4MB L2/1066MHz FSB

$316

AMD Athlon 64 X2 4600+

2.4GHz/2x512KB L2

$301

AMD Athlon 64 X2 4200+

2.2GHz/2x512KB L2

$240

Intel Core 2 Duo E6400

2.13GHz/2MB L2/1066MHz FSB

$224

Intel Core 2 Duo E6300

1.86GHz/2MB L2/1066MHz FSB

$183

AMD Athlon 64 X2 3800+

2.0GHz/2x512KB L2

$169

Intel Pentium D 945

3.4GHz/2x2MB L2/800MHz FSB

$163

AMD Athlon 64 X2 3600+

2.0GHz/2x256KB L2

$139

Intel Pentium D 915

2.8GHz/2x2MB L2/800MHz FSB

$133

Intel Pentium D 820

2.8GHz/2x1MB L2/800MHz FSB

$113

Intel Pentium D 805

2.66GHz/2x1MB L2/533MHz FSB

$93

Note that this table is based on unofficial data that is why we do not claim that the listed prices are absolutely correct and final.

Note that Intel is going to move all processors based on the old NetBurst microarchitecture into a different price group having turned them into something like “mobile Celeron” family. The top Pentium D models will be discontinued, Pentium D 945 will take over their position in the chart. This CPU will work at 3.4GHz and will not support Virtualization technology. It will become the fastest Pentium D model, although it will sell cheaper than the youngest Core 2 Duo processor.

As for the AMD CPU pricing, it will also go down, however, the price on the youngest CPU models will not drop to the level of the youngest dual-core solutions from Intel. Even taking into account the upcoming launch of the Athlon 64 X2 3600+ “lite”.

The price chart allows us to clearly determine the dual-core competitors to our Core 2 Duo E6300. They are Intel Pentium D 945 and AMD Athlon 64 X2 3800+. They will be the main opponents to our today’s hero.

As a result, our test platform will look as follows:

CPUs:

AMD Athlon 64 X2 3800+ (Socket AM2, 2.0GHz, 2x512KB L2);

Intel Core 2 Duo (LGA775, 1.86GHz, 2MB L2);

Intel Pentium D 945 (LGA775, 3.4GHz, 2x2MB L2).

Mainboards:

ASUS P5W DH Deluxe (LGA775, Intel 975X Express);

ASUS M2N32-SLI Deluxe (Socket AM2, NVIDIA nForce 590 SLI).

Memory:

2048MB DDR2-800 SDRAM (Mushkin XP2-6400PRO, 2 x 1024 MB, 4-4-4-12).

Graphics card: PowerColor X1900 XTX 512MB (PCI-E x16).

Storage subsystem: Maxtor MaXLine III 250GB (SATA150).

OS: Microsoft Windows XP SP2 with DirectX 9.0c.

The tests were performed with the mainboard BIOS setup for maximum performance.

We tested the CPUs in nominal mode as well as in overclocked mode, so that you could get better idea of the performance improvement you may actually count on if you overclock your Core 2 Duo E6300. We will also provide the results obtained from the Core 2 Duo E6300 CPU overclocked to 2.94GHz; of Athlon 64 X2 3800+ CPU overclocked to 3.0Ghz and of Pentium D 945 CPU overclocked to 4.2GHz.

Performance

Synthetic Benchmarks

First of all we decided to check out the performance of our testing participants in simple synthetic benchmarks that do not use multi-threaded processing. The winner in both these tests is the CPU on Core microarchitecture working at its nominal speed as well as the overclocked one. And the advantage of this CPU is more than significant.

The results of the newer Futuremark 3DMark06 test are not so unified any more. Yes, Core 2 Duo E6300 performs quite well here, especially when we overclocked it and all the other participants were lost far behind. However, in the CPU subtest we see that Pentium D 945 outperforms the newcomer working at its nominal speed. I have to point out here that this dual-core processor family based on NetBurst architecture has also gained quite a bit of performance after the Core 2 Duo launch. However, they owe this improvement not to the architectural changes but to the price reduction that shifted them to a new segment. For example, Pentium D 3.4GHz used to sell for $316, and starting today it competes within the sub-$200 price range.

ScienceMark 2.0 is one of the few benchmarks that can be a consolation to AMD today. This tests uses the FPU unit and system memory a lot, and these particular operations have always been a trump of Athlon 64 processors. They process these commands even faster than the newly launched Intel Core based processors. However, the overclocked Core 2 Duo E6300 takes the performance advantage away from Athlon 64 here.

Gaming Applications

If Athlon 64 processors used to outperform their competitors in 3D games quite tangibly, now we can say the same about Core 2 Duo. E6300 processor working at its nominal speed appeared faster than Athlon 64 3800+ in most games: 6.8% faster in Quake 4, 7% faster in F.E.A.R., 18% faster in half-Life 2 and 18.7% faster in Far Cry. After overclocking, the situation looks even rosier for this processor: Core 2 Duo is an indisputable absolute leader.

Audio and Video Encoding

Once again Core 2 Duo shows better results than all other CPUs from the same price range. This is actually not surprising at all. At the same time, we can point out that Pentium D 945 outperformed Athlon 64 3800+ in this test, too.

Image and Video Editing

The situation here is exactly the same as in media content encoding tasks. Intel Core 2 Duo E6300 is far ahead of its competitors. Overclocking only adds up to the gap between them.

Archiving

WinRAR performance chart looks exactly the same as the previous ones.

Professional OpenGL and Final Rendering

Results of professional applications do not reveal anything new to us. We can only once again admire the results of Intel CPUs on Core microarchitecture, especially those of the overclocked processor. At the same time we would like to mention that Pentium D 945 also proved very fast in applications of this type.

Conclusion

First of all I would like to point out that new Intel processors on Core microarchitecture boast very impressive performance. The improvements Intel introduced in them have certainly helped create today’s most efficient x86 processor design. And the results of our Core 2 Duo E6300 tests prove it. Although the newcomer works at lower nominal clock speed than AMD Athlon 64 X2 3800+, it demonstrates absolute advantage in most applications. Therefore, if AMD doesn’t drop the prices of its dual-core processors even lower (which is unlikely so far), we will have to state that Intel offers a way better price-to-performance ration for the mainstream and high-end segment.

And Overclocking wouldn’t help here. As we have just seen in this article, the youngest Core 2 Duo models boast very good overclocking potential. In fact, it is much better than that of other CPUs from the same price range. During our test session we managed to overclock Intel Core 2 Duo by more than 50% without touching its Vcore and using an air cooler. However, we didn’t even come close to revealing its entire overclocking potential, because of the hardware-related issues of the platform we used.

As we have already said, Core 2 Duo processors have their clock frequency multiplier locked at a relatively low value. As a result, the mainboards used for overclocking experiments like that should allow increasing the FSB frequency quite significantly. Unfortunately, the ASUS P5W DH Deluxe mainboard we used could only support 420MHz FSB frequency. That is why we didn’t manage to get more impressive results. Although, what we achieved was quite remarkable already, I should say.

This way, Core 2 Duo E6300 processor can be regarded as a great choice within its price group. However, when you build a system around it, you should pay special attention to the mainboard you pick, because it will determine your maximum overclocking potential. Therefore, smart mainboard choice is a crucial moment when putting together a system with Intel Core microarchitecture based processor.